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Despite being often used by Mario and his friends as helpful means of attack, fireballs are sometimes encountered as stand-alone obstacles. Their first appearance, Mario Bros., is also the first time they were depicted as independent enemies.
In Mario Bros., fireballs are unique enemies in that game in that they cannot cross the left or right edge of the screen and come out on the other side. Together with Icicles, they are also the only enemies that can harm players hiding behind the bottom pipes.
Fireballs come in red and green varieties. The red fireballs are slower and bounce diagonally all around the stage. If they hit one side of the screen, they ricochet off the side and keep going until making a full circuit of the screen after which they will disappear and respawn as a faster opponent. The quicker green Fireballs move horizontally from one side of the screen to the other where it will disappear until respawning elsewhere. It has a pattern of two small wavy bounces and one long bounce. To destroy Fireballs, the player has to bump them from below while they are touching the platform or the player could also use a POW Block to defeat them as well. Fireballs respawn as faster enemies a few moments after being destroyed. There can be a maximum of four fireballs, two of each color, on screen at any one time.
In other iterations of Mario Bros.
In Super Mario Bros. 3, there is a 2 player minigame which has Fireballs in it. In Super Mario All-Stars, the Battle Mode has both fireballs using the red sprite while the battle game perplexingly replaces the sprites with Boos. Red Fireballs can also now go through the wrap-around screen.
Fireballs appear in Luigi Bros.; an additional game featured in Super Mario 3D World. Like the other enemies in Luigi Bros., Fireballs behave in the same way as Mario Bros., which this game is based on.
In Wrecking Crew, a Fireball will appear if too much time is spent in one place. It acts like the red ones in the previous appearance; green versions are absent.
Donkey Kong Country Returns / 3D
In both Donkey Kong Country Returns and Donkey Kong Country Returns 3D, fireballs are featured as hazards during a short section of Hot Rocket. They come out from behind and fly across the screen, destroying the Kongs' Rocket Barrel and causing them to lose a life if they come into contact. However, if avoided, fireballs simply outrun the characters, never to be seen again. Fireballs cannot be stopped or destroyed. At one point, a fireball crashes into a chunk of rock falling from the ceiling, destroying it and revealing a Puzzle Piece.
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